CES Soil Contamination & Remediation 3

Question 1

During a Phase II Environmental Site Assessment, which activity is typically performed?

Accepted Answer

Collection of soil and groundwater samples for laboratory analysis

Answer

Phase II ESAs involve intrusive investigation — collecting and analyzing environmental samples (soil, groundwater, soil gas) to confirm or characterize contamination identified or suspected in Phase I.

Question 2

Polychlorinated biphenyls (PCBs) persist in soil primarily because they:

Accepted Answer

Are hydrophobic and strongly sorb to soil organic matter, resisting biodegradation

Answer

PCBs are highly hydrophobic compounds that partition strongly onto soil organic matter and are resistant to microbial degradation, resulting in long environmental persistence.

Question 3

In situ chemical oxidation (ISCO) using potassium permanganate is LEAST effective for treating which contaminant class?

Accepted Answer

Saturated chlorinated alkanes (e.g., TCA)

Answer

Potassium permanganate effectively oxidizes compounds with carbon-carbon double bonds (alkenes, aromatics) but reacts poorly with saturated chlorinated alkanes such as 1,1,1-TCA.

Question 4

Which of the following describes a Dense Non-Aqueous Phase Liquid (DNAPL)?

Accepted Answer

A chlorinated solvent denser than water that sinks through the saturated zone

Answer

DNAPLs, such as PCE and TCE, are denser than water and sink vertically through the unsaturated and saturated zones until they reach an impermeable layer, making them difficult to locate and remediate.

Question 5

The concept of 'risk-based corrective action' (RBCA) for contaminated sites prioritizes:

Accepted Answer

Cleanup levels tied to site-specific exposure scenarios and acceptable risk levels

Answer

RBCA establishes site-specific cleanup standards based on actual exposure pathways, receptor populations, and target risk levels rather than applying universal background or detection-limit-based standards.

(CES) Certified Environmental Scientist Practice Test

(CES) Certified Environmental Scientist Practice Test

CES Soil Contamination & Remediation 3